On an 84 300D is not difficult but time consuming.
My suggestion is do not screw in but do not tighten both of the large Motor Mount Bolts. I had trouble alighning one of the becaues I tightened the other side. I buggered the thread in the Aluminum Motor Mount arm. Luckly I had a metric tap that Size and was able to clean up the threads.
You might want to take a look at the Diesel Giant site. He has some tools he sells to make the job easier. You do not have to buy these tools as you can cut your own Allen Wrench to shorten it.
I was able to get at mine without shorteing an Allen wrench as I used a Socket with an Allen Wrench on the end and a U-joint/extension and Socket Wrench. Take a look and see what type of room you have.
Take a good look at your Motor Mounts right now; if they compress it is possible for the Power Steering Belt to cut through one of the Engine Oil Cooler Hoses.